A prosecuting attorney greeted the jury in the George Zimmerman trial Monday with a quote full of expletives , while his adversary decided it was appropriate to tell jurors a knock-knock joke .

And that was just the beginning of opening statements in Zimmerman 's long-anticipated murder trial .

In a case that has ignited national debate about gun laws and race relations , Zimmerman , a neighborhood watch captain , is accused of second-degree murder in the fatal shooting of 17-year-old Trayvon Martin in February 2012 in Sanford , Florida .

Prosecutor John Guy 's first words to the six-woman jury may have raised a few eyebrows .

`` Good morning . ` F ***** g punks , these a ****** s all get away , ' '' Guy quoted Zimmerman . `` These were the words in this grown man 's mouth as he followed this boy that he did n't know . Those were his words , not mine . ''

Zimmerman , Guy said , `` got out of his car with a pistol and two flashlights to follow Trayvon Benjamin Martin , who was walking home from a 7-Eleven , armed '' with a fruit drink and a bag of candy . Eventually the two became entangled on the ground in a fight . A witness has said Martin was on top of Zimmerman , Guy said .

`` The defendant claims that while Trayvon Martin was on top of him , he said , ` you are going to die tonight , ' '' said Guy . `` Nobody heard that . ''

Guy told jurors that no witnesses saw what happened the night of the shooting from beginning to end . Witnesses only saw `` slices '' of what happened , he said .

`` We are confident that at the end of this trial you will know in your head , in your heart , in your stomach that George Zimmerman did not shoot Trayvon Martin because he had to , '' Guy said . `` He shot him for the worst of all reasons , because he wanted to . ''

Fast facts : Trayvon Martin shooting

In the first day of testimony , jurors heard witnesses recount Martin 's trip to the convenience store , Zimmerman 's call complaining about a suspicious person walking through his neighborhood before Martin 's killing , and a call from the previous August , in which Zimmerman reported an alleged burglary to police .

Proceedings ended for the day when defense attorney Mark O'Mara objected to the earlier call , which prosecutors argued was necessary to explain Zimmerman 's remark about burglars who `` get away . ''

The Martin family sat watching the proceedings behind State Attorney Angela Corey . Before witness testimony began , Judge Debra Nelson denied a defense request that Martin 's father , Tracy Martin , leave the courtroom .

Tracy Martin is a potential witness , and potential witnesses can be forced to sit outside of the courtroom to keep their testimony from being tainted by other witnesses . But the next-of-kin of victims are allowed to remain in court even if they 're expected to testify .

O'Mara also accused Tracy Martin of using an obscenity toward a friend of Zimmerman 's while holding the door for him during a hearing two weeks ago . The friend , Timothy Tucholski , testified that he had n't wanted to make an issue of it before .

`` I was n't planning on coming up here . I do n't want to be sitting here , '' he said .

But Nelson denied the request , and Martin remained in court -- but Zimmerman 's parents were covered by the rule regarding potential witnesses and had to sit outside , as did Benjamin Crump , the lawyer for Martin 's parents .

At one point , Martin 's father began crying as Guy detailed how officers tried to save his son 's life . Zimmerman has mostly stared straight ahead without any signs of emotion .

Following Guy 's statement , defense attorney Don West came forward to woo the jury . As he began , he told a knock-knock joke . But it failed to win a laugh . `` Knock knock . Who 's there ? George Zimmerman . George Zimmerman who ? Good , you 're on the jury , '' he said . Later , West apologized . `` No more bad jokes , I promise that , '' he told jurors . `` I was convinced it was the delivery . ''

West quickly got on with the business of making his case : that Zimmerman was forced to act in self-defense to save his own life .

`` The evidence will show this is a sad case ; no monsters here . ... George Zimmerman is not guilty of murder . He shot Trayvon Martin after he was viciously attacked . ''

With the help of PowerPoint visuals , West spent hours hammering home his argument .

He broke down Zimmerman 's 911 call in which he first reported seeing Martin and told about following him .

`` Little did George Zimmerman know at the time in less than 10 minutes from him first seeing Travyon Martin that he , George Zimmerman , would be suckered punched in the face , have his head pounded on concrete and wind up shooting and tragically killing Trayvon Martin , '' West told jurors .

West also deconstructed a 911 call a neighbor made , in which it is possible to hear screams and a shot in the background that West said was the sound of the fatal bullet .

As the dramatic recording audio filled the courtroom , Zimmerman showed no emotion . Martin 's mother left the courtroom .

`` At the moment this actually became physical was that Trayvon Martin -- I will use my words -- that Trayvon Martin decided to confront George Zimmerman , '' West said . `` That instead of going home . He had plenty of time . This is , what , 60 or 70 yards . Plenty of time . He could 've gone back and forth four or five times . ''

West quoted a witness named John Good who described the fight . `` He called it a ` ground and pound ' by Martin , who he said was on top of Zimmerman , beating him . ''

`` He saw enough that this was serious , '' West said . Zimmerman cried out for help , looked at Good and said , `` help me . '' But the beating continued while Good went inside his home to call 911 , West said .

There was a shot . Shortly afterward , according to West , Zimmerman said Martin `` was beating me up , and I shot him . ''

West also disputed the prosecution 's claim that Martin was unarmed .

`` Travyon Martin armed himself with the concrete sidewalk and used it to smash George Zimmerman 's head , '' said West . `` No different than if he picked up a brick or smashed his head against a wall . That is a deadly weapon . ''

West showed jurors photos taken of Zimmerman after the fight . `` What you can really see in these pictures that you will have in evidence are the lumps , '' West said . `` The big knots on each side of his head . Consistent with having his head slammed into concrete . ''

All-female jury to try Zimmerman

Among the first prosecution witnessed called was the 911 dispatcher who took Zimmerman 's call before the shooting . Seat Noffke testified that he was trained to give general commands instead of direct orders to people .

When Zimmerman said he was following Martin , Noffke told him , `` Okay we do n't need you to do that . '' Noffke told the prosecutor he 's liable for any direct orders he gives someone .

On cross-examination , defense attorney O'Mara pointed out that Noffke asked Zimmerman , `` Which way is he running ? ''

`` If you tell somebody twice to let you know if the person that they 're concerned about is doing anything else -- do you think they 're going to keep their eye on them ? '' asked O'Mara .

`` I ca n't answer that , '' said Noffke .

`` You did tell him twice to let you know if that guy did anything else , '' said O'Mara .

`` Yes sir , '' said Noffke .

Noffke went on to say he only wanted a location of the suspect for officers and that he never told Zimmerman to follow or keep his eye on Martin .

Shortly before court got under way , Martin 's mother , Sybrina Fulton , spoke to reporters , asking people to `` pray for me and my family because I do n't want any other mother to experience what I 'm going through now . ''

Judge : No state expert testimony on 911 calls

Martin was black , and Zimmerman identifies himself as Hispanic .

In a CNN poll released Monday morning , 62 % of respondents say the charges against Zimmerman are probably or definitely true .

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Defense lawyer apologizes for telling joke during opening statements

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Father of Trayvon Martin cries in courtroom ; George Zimmerman shows no emotion

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Did Zimmerman commit 2nd degree murder when he killed Martin ? Or was it self-defense ?

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62 % in a CNN poll say the charges against Zimmerman are `` probably '' or `` definitely '' true